Process of refining hydrocarbon oils with copper salts



A. LACHMAN 1,826,139

PROCESS OF REFINING HYDROCARBON OILS WITH CADMIUM SALTS Oct. 6, 1931.

Original Filed May a. 1929 ATTORNEY Patented Oct. 6, 1931 UNITED STATESPATENT OFFICE ARTHUR LA GHMAN, OF BERKELEY, CALIFORNIA, ASSIGNOR TORICEFIELD OIL COM- rm CALIFORNIA, OF LOS ANGELES, CALIFORNIA, ACORPORATION OF DELA- WARE PROCESS OF REFININ' G HYDROCARBON OILS WITHCOPPER SALTS Original application filed Kay 8, 1929, Serial No. 361,513.Divided and this application filed lay 8, 1929. Serial No. 361,514.

This invention relates to a process of purifying and refininghydrocarbon oils obtained by distillation or cracking of mineral oils,such as lubricating oils, lamp oils, gasoline stocks or distillatesderived from oil shale.

This application is a division of my application for process of refininghydrocarbon oils, executed April 20, 1929, Serial No. 361,513, filed May8, 1929, which consists of asimilar method or process for purifying andrefining mineral oil products with soluble metal salts.

The process of refining hydrocarbon oils, as described in thisapplication, is applicable to all-mineral oil products derived bydistillation or cracking operations, such as lubricating oils, lamp oilstocks, gasoline stocks, distillates derived from oil shale, etc., andis particularly adaptable to gasoline stocks obtained by cracking higherboiling hydrocar- 2; bon oils. For the purpose of simplifying thedescription, reference will be made to gasoline only.

Crude gasoline stocks obtained by distilling or cracking petroleum oilsconsist of amixture of saturated and unsaturated hydrocarbons togetherwith sulphur compounds, nitrogen bases and other substances of anundefined nature. These latter substances are readily oxidizable atordinary temperatures and are usually responsible for the change ofcolor which takes place when refined gasoline is stored. Theseoxidizable substances are removed with difliculty when gasoline stocksare treated by the methods known in common use.

c In order to show the nature of my invention, it is desirable todescribe the method now in common use in oil refineries, andparticularly that step of refining gasoline stocks which consists indeodorizing and stabilizing the same. Crude gasoline stocks obtained bydistillation of crude petroleum oil or by cracking a higher boilingpetroleum oil, are customarily treated with approximately from 1 percent to as high as 8 percent by weight sulphuric acid. the quantity ofsulphuric acid depending upon the nature of the gasoline stock to betreated and the product desired. This acid treatment usually consists incommingling the gasoline stock with the required amount of sulphuricacid necessary to obtain the desired extraction, either by thewell-known batch or'continuous treatment, after which the products ofthe acid reaction are permitted to settleand then withdraw from thetreated gasoline stock. The acid treated gasoline stock is thenneutralized by washing with a water solution of an alkali and finallywith water. This treatment removes most of the impurities, butsubsequent treatments are usually necessary to deodorize and remove orconvert corrosive sulphur compounds into non-corrosive bodies. For thispurpose, a water solution of sodium plumbite or sodium hypochlorite isusually employed to render the gasoline sweet to the doctor test.

The general objections to a treatment of this character are as follows:

(1) Gasoline purified by this method freequently becomes discolored whenstored for a riod oftime; a

(2) Considerablevquantities of sulphuric acid are required, which arediflicult to recover;

(3) As high as 10 per cent of the valuable stable unsaturatedhydrocarbons contained in the gasoline stock may be lost; and

(4) The treatment must frequently be followed by a deodorizing orsweetening process, such as that heretofore described.

Now, I have discovered that the sulphuric acid normally used to treatcrude gasoline stocks may be reduced to a high extent, and in many casesmay be entirely eliminated by the employment of a water solution ofcertain metallic salts, or mixtures of the same, which maybe zinc,copper, cadmium, mercury, iron, chromium, manganese, aluminum, nickel orcobalt water soluble salts, such as the chloride, bromide, iodide,sulphate, nitrate, and also any of the water soluble salts of the abovenamed metals of organic acids, such as the sulphonic acids of benzol,toluol and xylol, or the sulphonic acids derived from the treatment ofpetroleum oils with sulphuric acid.

The process described briefly consists in passing the hydrocarbon oilproduct such as gasoline stock while in a vapor state, through or incontact with a hot concentrated water 100 solution of any of theaforesaid metallic salts or mixtures thereof. The gasoline stool: sotreated is usually pure enough for immediate use, although it sometimesmay contain small amounts of hydrogen sulphide, which may be removed bywashing with an alkaline solution of sodium or calcium hydroxide, or thecarbonates of sodium or potassium.

'lhe hydrocarbon oil stool; to he treated by my invention may or may nothave had preliminary treatment with sulphuric acid, or other agents topartly purify the same, or may be first partly purified by my inventionand the purifications completed by methods known in the art, such astreatment with caustic alkali, sulphuric acid, etc. In case of gasolinestocks produced by cracking high sulphur bearing crude petroleum oils orresiduums, it may be advantageous to treat such gasoline stocks withsmall amounts of sulphuric acid before the treatment witha concentratedwater solution ofany of the aforestated metallic salts, which may alsobe followed by treatment with an a lraline water solution of sodium,potassium or calcium hydroxide, or the carbonates of sodium orpotasslum.

Although a solution of less concentration may be employed which mayrange from 50 or less to approximately per cent, the strength of thewater solution of the metallic salt or mixture of salts employed ispreferably a substantially concentrated solution, and the temperatureemployed "for the treatment is approximately 300 to 4200 degrees E,which normally fluctuates, depending upon the vaporizing temperature ofthe oil under treatment.

With the foregoing preliminary explanation, the preferred embodiment ofmy invention will now be more fully explained by reference to theaccompanying drawing which is a diagrammatic view of one form ofapparatus which may be employed for carrying out the objects of thepresent invention.

Referring to the drawing, 2 indicates a pipe leading to a source ofcrude gasoline vapors not shown, such as a fractionating tower employedto separate the lower boiling 011s from the higher boiling oils. Bindicates a tower of suitable height and diameter filled w1th resistantor contact material, such as fire brick, spiral tile or the like,indicated at 3, which forms numerous tortuous passages through thetower, although it is to be understood that the'well-lrnown bubble capcontact tower may be employed. Disposed above the tower or adjacent tothe same, is a tank 12 containing a substantially concentrated watersolution of a metallic salt or mixtures of the same, as heretoforeenumerated, having a concentration of from 50 per cent or less to ashigh as approximately 85 per cent. This tank is connected to the top ofthe tower by means of a pipe having a regulating valve This p'peterminates over a spreader plate 6 and this plate evenly distributes thewater solution of the metallic salt or salts when the valve 5 is opened,over the brick worlr or contact material. The water solution of themetallic salt or salts flows downward through this contact material andmay finally be discharged through the bottom by a pipe 7, after which itis treated for recover The tower B is also provided with a steam orwater inlet pipe 8, which intermittently or continuously plies apredetermined amount or" water or steam to the tower. The hot gasolinevapors .c U

irom the pipe 2 enter the lower end or me tower B at a point 9-. lhe oilvaoors pass up through the numerous contact passages in the brick workand thereby come into inti' mate contact with the said water solution ofmetallic salt or salts flowing over the same. Although othertemperatures may be employed, both the water solution of metallic saltor salts and oil vapors are generally maintained a temperature ofapproximately 300 to 400 degrees F, and the oil vapors are discharged atthe upper end of the tower through a pipe 10 which is connected with acondenser ll of suitable construction. The gasoline vapors passingthrough the contact tower B at the temperature specified. vaporize acertain amount of water from the water solution of metallic salts andthe purpose of the steam or water inlet pipe'8 is that of continuouslymaintaining the solution at a certain water content so as to maintainthe necessary fluidity which is essential for good contact between therising gasoline vapor and the down-flowing water solution of metallicsalt or salts. Preferably the concentration of the water solution ofmetallic salt or salts is maintained at its predetermined'limits ofconcentration by a continuous introduct on of water or water vapor.Otherwise solid metallic salt or salts and solid sludge impurities mavplug the passages through which the gasoline vapors are being conducted.

While not always necessary, it is beneficial that the water solution ofmetallic salt or salts contain hydroxides or oxides of anv of themetals. or mixtures thereof, heretofore enumerated. before beingintroduced into the system. This mav be accomplished bv agitating thewater solution of the metallic salt or salts with any of the hydroxidesor oxides of any of the numerated metals. The optimum amount of themetal oxide or hydroxide ranges from about of l per cent to 3 per centby Weight of the water solution of metallic salt or salts. Inexplanation, when the oxides or hydroxides of any of the aforementionedmetals or mixtures thereof are soluble in substantial amounts in thesalt or salts solutionat the temperatures and pressures employed, thebeneficial purification action will be enhanced, but even if nosubstantial solubility exists, useful effects can be obtained if theoxides and hydroxides are suspended in the salt or salts solution.

The reaction tower B is kept full of the water solution of the metallicsalt or salts containing metallic hydroxides or oxides such as zinchydroxides, and a fresh supply of approximately 15 pounds of the saidsolution is admitted for each barrel of gasolinestock under treatmentand a corresponding amount of the spent solution is withdrawn at thesame time.

The amount of water vapor required toreplace the vaporized water fromthe water solution of metallic salt or salts varies within wide limits,depending upon the concentration of the solution employed, thetemperature at which the operation is carried out and the nature andamount of inert gases which may accompany the gasoline vapor beingtreated. By this treatment the major portion of the impurities containedby the ga soline stock is removed and carried out with the watersolution of metallic salt or salts as a sludge'and the purified gasolinevapors, when condensed, are suitable for use as a refined gasoline stockof high purity.

While the process herein described is well adapted for carrying out theobjects of the present invention. it is to be understood that variousmodifications and changes may be made without departing from theinvention. such for example as the use of centrifugal or othermechanical mixers or the employment of any of the well-known contacttowers wherein a water solution of a metallic salt or mixtures ofmetallic salts, either organic or inorganic, heretofore enumerated, maybe commingled with or brought into contact with a petroleum oil vapor atthe reactin temperatures and the invention includes all suchmodifications and changes as come within the scope of the appendedclaims.

What I claim is:

1. A process of refining m neral oils. comprising, vaporizing a mineraloil, 'cofitactin" the vaporized oil with a water solut on of a coppersalt maintained in solution and then condensing purified oil vaporseparated from products of reaction and treating agent.

2. A process of refining mineral oils. comprising, vaporizing a mineraloil bv the application of heat, contacting the heated vaporized mineraloil with a substantially concentrated water solution ofa' copper saltand then condensing purified oil vapor separated from products ofreaction and treating agent.

3. A process of refining mineral oils, comprising, vaporizing a mineraloil, contacting the vaporized mineral oil with a water solution of amixture of copper salts main tained in solution, and then condensingpurified oil vapor separated from products of reaction and treatingagent.

4. A. processof refining mineral oils, comprising, vaporizing a mineraloil by the application of heat. contacting the heated vaporized mineraloil with a heated water solu tion of a copper salt maintained insolution, and then condensing purified oil vapor separated from productsof reaction and treating agent.

5. A process of refining mineral oils. comprising, vaporizing a mineraloil by the application of heat, contacting the heated vaporized mineraloil with a water solution of a' copper salt maintained in solution andheated to a temperature of not less than the vaporizing temperature ofthe vaporized mineral oil under treatment, and then condensing purifiedoil vapor separated from products of reaction and treating agent.

6. A process of refining mineral oils, comprising. heating a mineral oilto form a vapor. at temperatures of approximately 300 to 400 degrees F..contacting the heated vanor with a water solution of a copper saltmaintained in solution at a substantially similar temperature, and thencondensing purifield oil vapor separated from products of reaction andtreating agent.

7. A process of refining mineral oils. comprising. heating a' mineraloil to form a vapor at temperatures of approximatelv 300 to 400 degreesF., passing the heated vapor through or in contact with a water solutionof copper salts maintained in solution at a substantially similartemperature and having a concentration of approximately 50- 85% and thencondensing purified oil'vapor separated from products of reaction andtreating agent.

8. A process of refining mineral OllS, comprising. heating a mineral oilto form a vapor, contacting the heated vapor with a water solution ofcopper salts maintained in a fluid condition, and containing copperoxide, and then condensing purified oil Vapor separated from products ofreaction and treating agent.

9. A process of refining mineral oils, compising, heating a mineral oilto form avapor, passing the heated vapor through and in contact with awater solution of copper salts, maintaining the solution in a fluidcondition by the addition'of water during contact of the vapor with thetreating solution and condensing the vapor'aft-er passing through thesolution. l 10. A process of refining mineral oils, comprising,commingling the vapor of a mineral oil with a water solution of a coppersalt maintained in a fluid condition, and then con-'v densing purifiedoil vapor separated from products of reaction and treating agent.

11. A process ofrefining mineral oils, com prising, heating a mineraloil to form a vapor, passing the heated vapor through and in contactwith a Water solution of a copper salt containing copper oxide,maintaining the solution in a fluid condition by the addition of waterand condensing purified oil vapor after passing through the solution.

12. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, passing the heated vapor through and in contactwith a water solution of copper salts, containing from A; of 1 per centto 3 per cent by weight of copper oxides, 1naintaining the solution in afluid condition by the addition of water and condensing purified oilvapor after passing through the solution.

13. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, passing the heated vapor through and in contactwith a watersolution of copper salts, maintaining the concentration ofthe solution within predetermined limits by the addition of Water duringcontact of the vapor with the .treating solution, and condensing thevapor after passing through the solution.

14. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, at temperatures of approximately 300 to 400 degreesF., passing the heated Vapor through and in contact with a watersolution of a copper salt maintained at a similar temperature and havinga concentration of approximately 5085%, maintaining the concentration ofthe solution as specified by the continuous addition of water duringcontact of vapors with the treating solution, and then condensing thevapor after passing through the solution.

15. A process of refining mineral oils, comprising, vaporizing a mineraloil, contacting the vaporized oil with a water solution of a coppersalt, intermittently introducing water into the solution of copper saltto maintain the aqueous solution and continuously condensing the vaporsof the purified mineral oil separated from the products of reaction andsolution of copper salt.

16. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, passing the vapor through and in contact with awater solution of copper salts containing copper oxide, intermittentlyintroducing water into the solution of copper salts to maintain theaqueous solution containing copper oxide and continuously condensing thevapors of the purified mineral oil separated from the products ofreaction and solution of copper salts containing copper oxide.

17. A process of refining mineral oils, comprising, heating a mineraloil to form a vapor, passing the vapor through and in contact with awater solution of a copper salt contaming copper oxide, intermittentlyintroducing Water into the solution of copper salt In testimony whereofI afiix my signature.

ARTHUR LACHMAN.

